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Heterodontus japonicus
Heterodontus japonicus (''Japanese bullhead shark)' Kingdom: '''Animalia Phylum: Chordata Class: Chondrichthyes Order: Heterodontiformes Family: Heterodontidae Genus: Heterodontus Species: Heterodontus japonicus Environment: milieu, climate zone, depth range, distribution range: Marine; demersal; depth range 6 - 100 m. Subtropical; 43°N - 23°N, 118°E - 143°E. Distribution: Northwest Pacific: off Japan, Korean Republic, northern China including Taiwan Island. Size, weight, age: Max. length: 1.20 m; weight: ?'; age: '? Short description: A modest-sized shark reaching a maximum known length of 1.2 m (3.9 ft), the Japanese bullhead shark has a cylindrical body with the short, wide head and blunt, pig-like snout typical of the bullhead sharks. The eyes lack a nictitating membrane and are followed by tiny spiracles. Shallow supraorbital ridges are present above the eyes, and the space between them is slightly concave. The nostrils are divided into incurrent and excurrent openings by long flaps of skin that reach the mouth; the incurrent opening is encircled by a groove while another groove runs from the excurrent opening to the mouth. The small mouth is positioned nearly at the tip of the snout; the front teeth are small with a sharp central cusp flanked by a pair of lateral cusplets, while the back teeth are broad and rounded. There are deep furrows at the corners of the mouth, extending onto both jaws. The first dorsal fin is very large and high, and is somewhat falcate (sickle-shaped); it originates over the bases of the pectoral fins. The second dorsal fin is much smaller, but similar in shape, and originates over the rear tips of the pelvic fins. Both dorsal fins bear stout spines on their leading edges. The pectoral fins are large; the pelvic fins are much smaller than the first dorsal fin. The anal fin is placed well in front of the caudal fin, which is broad with a short lower lobe and a long upper lobe bearing a strong ventral notch near the tip. The dermal denticles are large and rough, particularly on the sides of the body. The coloration is light brown, with a series of diffuse-edged, darker wide bands interspersed with narrower stripes from snout to tail, numbering 11–14 in all. A faint lighter band is on top of the head between the eyes, and a darker blotch is beneath each eye. Biology: Found near shore on the continental shelf, more commonly on rocky and kelp-covered bottom. Feeds on crustaceans, mollusks (including top shells), small fishes and sea urchins. Oviparous. Grabs prey by protruding its jaw with considerable distance. Life cycle and mating behavior: Oviparous. Eggs are laid in rocks or in kelp at depths of about 8 or 9 m and are present from March through September. Eggs are more abundant, however, in March and April. Eggs are hatched in about a year; size at hatching is about 18 cm. There may be a `nest' for several females laying eggs but this is not a true nest. A female lays two eggs at a time, for 6 to 12 spawnings. Main reference: Compagno, L.J.V., 1984. FAO Species Catalogue. Vol. 4. Sharks of the world. An annotated and illustrated catalogue of shark species known to date. Part 1 - Hexanchiformes to Lamniformes. FAO Fish. Synop. 125(4/1):1-249. Rome, FAO. IUCN Red List Status: LEAST CONCERN (''LC)' '''CITES: Not Evaluated CMS: Not Evaluated Threat to humans: Traumatogenic Human uses: Fisheries: minor commercial. Category:Heterodontidae, Bullhead, horn, or Port Jackson sharks